Sensory specific satiety: yup that sums up the problem with my cooking.
When you think of garnish, you probably picture a sprig of parsley or mint, a sad radish rose, a carrot curl, or doodle of sauce, or some barely edible flower that has decorated plates for a hundred years – and still does in some quarters. If so, I'm guessing you don't spend a lot of time on them for your average homecooked meal. The purpose this type of garnish serves is purely visual, and the aesthetics are dubious at best.